Can streptavidin leak from the Streptavidin-Coupled Dynabeads®?
• The streptavidin molecule is covalently attached to the bead’s surface. However, not all of the four streptavidin subunits are covalently coupled to the beads, typically only one or two. Streptavidin is like other proteins; if heated it can denature and dissociate into subunits. If streptavidin-coupled Dynabeads are boiled, some of the streptavidin subunits may be released (as monomers or aggregates) from the beads. The covalently bound streptavidin subunits will not be affected by such treatment. When streptavidin is bound to biotin, the streptavidin-biotin complex is more stable than the streptavidin itself. Under normal, recommended conditions, only negligible leakage of streptavidin from the beads is detected (less than 0.2% of total attached streptavidin after 2 months at 37°C).
